To reduce equipment cost and running cost required when by-product water generated as a by-product of liquid hydrocarbon in the Fischer-Tropsch (FT) process is purified and converted into water which can be used for various purposes.
Wet oxidation treatment (1) is applied to by-product water separated from reactants obtained by the production of hydrocarbons using synthesis gas to obtain primary treated water. Subsequently, semipermeable membrane separation treatment (2) is applied to the primary treated water to obtain purified water. This purified water may be discharged to a river, sea, or the like, but is preferably used as industrial water, irrigation water, drinkable water, and the like. A part of concentrated water generated in the semipermeable membrane separation treatment (2) is returned to the by-product water to be subjected to the wet oxidation treatment again. Biological treatment and solid-liquid separation are applied to the remainder of the concentrated water to purify the concentrated water. This biologically treated water is returned, for example, to the semipermeable membrane separation treatment (2) to be treated again.
KAWAMURA KAZUSHIGE
OGI SATOSHI
KOSHIZUKA HIROMI
TAKAHATA HIROO
UEMURA TADAHIRO
TANIGUCHI MASAHIDE
TORAY INDUSTRIES
Susumu Ohata